Have read a few threads of people having a similar issue, but the fixes donít work. This is a new Sony Vaio, Windows 8. I installed Calibre ver. 0.9.7
I tried to add a pdf 2775 kb in size. Iíve used the program awhile and never saw a book take so long to add. Noticed the progression circle in the lower right corner was not moving. After 25 minutes I aborted. I canít get anything to add to the program, text files, pdf, mobi. Wonít add single books or by Folder. It will add an empty book.

I did uninstall the program and try 3 older versions, same results. I even logged in as Administrator, got the same results. Does Windows 8 not like the program?
Oh just got an error finally while adding 1 book:

ERROR: Adding failed: The add books process seems to have hung. Try restarting calibre and adding the books in smaller increments, until you find the problem book.